There is some benefit in registering multiple domain names. Protecting your brand would be one of the reasons to register variations of your website / business name not just for Australian domain names but also international (.com, .net, etc) and other country specific ones (.co.uk, .co.nz, etc).

Registering multiple domains have little or no effect on the Search Engine Optimisation (SEO) of a website. A primary domain with suitable keywords in them is more likely to help but this benefit is still very insignficant in comparison to writing good content regularly for your website.

1. Where can I register domain names and emails?
2. What can I optimise for search engines?

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